Low Coolant Level Warning...
Thread Starter
Junior Member
Joined: Jan 2015
Posts: 29
Likes: 0
From: NoVA
2015 GL450, 2014 BMW 640 xDrive Convertible
Low Coolant Level Warning...
My 2015 GL450 has less than 8500 miles. I keep getting warning of low coolant , but looking at the reservoir, it doesn't seem to be low. I read in other places that low wiper fluid can cause this error as well. My wiper fluids were low, so I put in about a half a gallon and it made the warning go away for about 5 days. I haven't used any wiper fluids during this time, now the warning is back on. Anybody else run into this?
Thanks
Thanks
MBWorld Fanatic!
Joined: Jan 2014
Posts: 1,055
Likes: 355
From: USA - Minnesota
2014 GL350
Yes, this is not that uncommon and there are numerous reports on this forum. The system has a VERY sensitive low level sensor and that sensor is not necessarily calibrated with the visual indicator.
It seems like the factory ships the trucks near the minimum fill level and then it takes a few thousand miles for the coolant to find its level within the system despite the fact the visual indicator remains within the normal range.
I bet you can have your dealer add a tiny amount and it will be fixed and you'll never have to worry about it again.
It seems like the factory ships the trucks near the minimum fill level and then it takes a few thousand miles for the coolant to find its level within the system despite the fact the visual indicator remains within the normal range.
I bet you can have your dealer add a tiny amount and it will be fixed and you'll never have to worry about it again.
Last edited by cadetdrivr; Oct 28, 2015 at 12:48 PM.
Super Member
Joined: Jul 2009
Posts: 814
Likes: 9
15 GL550
I'm on my second X166. Both have had this issue. Both have used coolant and you will need to add some every 5000 to 10000 miles. You can smell the coolant when the engine is hot and you stand beside the left front wheel which is near the reservoir. It's annoying but I purchased distilled water, MB coolant, and a pyrex measuring cup to periodically fill. As long as it only uses the coolant slowly, I'll add it myself. I don't want anyone tearing things apart to fix this. It could be as simple as a bad cap on the reservoir. Many of us have complained about this.
Super Member
Joined: Jul 2009
Posts: 814
Likes: 9
15 GL550
When the coolant is hot, it raises the level in the reservoir. That's why the low coolant warning goes off with a hot engine. You need to add about a cup of coolant/distilled water and you'll be good for another 5,000-10,000 miles.
Member
Joined: Apr 2003
Posts: 212
Likes: 0
From: Bay Area, CA
2015 GL550, 2019 GLC350e
I'm on my second X166. Both have had this issue. Both have used coolant and you will need to add some every 5000 to 10000 miles. You can smell the coolant when the engine is hot and you stand beside the left front wheel which is near the reservoir. It's annoying but I purchased distilled water, MB coolant, and a pyrex measuring cup to periodically fill. As long as it only uses the coolant slowly, I'll add it myself. I don't want anyone tearing things apart to fix this. It could be as simple as a bad cap on the reservoir. Many of us have complained about this.
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Thread Starter
Junior Member
Joined: Jan 2015
Posts: 29
Likes: 0
From: NoVA
2015 GL450, 2014 BMW 640 xDrive Convertible
I would think that only reason you would need to refill it on some interval is if there is a leak. Similar to Freon in AC units, both are closed system no? If you start dropping either, wouldn't it indicate a leak?
Oh well, I have the 10K service coming up so I will ask them the same.
Oh well, I have the 10K service coming up so I will ask them the same.
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Member
Joined: Sep 2009
Posts: 239
Likes: 2
From: SoCal
'15 GL450
Ours came on also at less than 10,000 miles. Easy DIY. While you are at it, I'd also check the turbo coolant (exact same type of coolant-red in color) located under the plastic engine cover. Mine was a little low also but not too bad. They must "under fill" the coolants when they ship these vehicles. Kind of a nuisance if you ask me.
Newbie
Joined: Apr 2012
Posts: 9
Likes: 2
From: Charlevoix,Mi
2014 GL450
I have a 2014 GL450. Since my dealer is 100 miles away, I looked to Amazon for coolant to have on hand - just in case a bit is needed to keep the levels topped off. Mine, like yours, is red(or pink) in color. All that I saw on Amazon was blue in color yet they have the MB 325.0 corrosion spec. Are the blue and the red(or pink) compatible if just a small amount would need to be added and mixed? If not, is there any source for the red other than the dealership?
Member
Joined: Sep 2009
Posts: 239
Likes: 2
From: SoCal
'15 GL450
I have a 2014 GL450. Since my dealer is 100 miles away, I looked to Amazon for coolant to have on hand - just in case a bit is needed to keep the levels topped off. Mine, like yours, is red(or pink) in color. All that I saw on Amazon was blue in color yet they have the MB 325.0 corrosion spec. Are the blue and the red(or pink) compatible if just a small amount would need to be added and mixed? If not, is there any source for the red other than the dealership?
Junior Member
Joined: Nov 2014
Posts: 71
Likes: 5
2013 GL450
i had the turbo coolant pipe issue couple of years ago and an indy shop replaced the pipe.
lately i have noticed a slow leak (last time when the coolant pipe went bad the leak was quicker, i'd refill and next day it would be low again), the low indicator would come on every a few months and i have been topping it up. lately i have noticed small puddle (not a lot maybe a few drops) on my garage floor semi-regularly (seems like if i leave the car there long enough i will see some), under the the driver side front pumper. looking under the hood i can see some liquid pooled on the tray around there. took it to another indy but the guy said he pressure tested it and can't find the leak?
lately i have noticed a slow leak (last time when the coolant pipe went bad the leak was quicker, i'd refill and next day it would be low again), the low indicator would come on every a few months and i have been topping it up. lately i have noticed small puddle (not a lot maybe a few drops) on my garage floor semi-regularly (seems like if i leave the car there long enough i will see some), under the the driver side front pumper. looking under the hood i can see some liquid pooled on the tray around there. took it to another indy but the guy said he pressure tested it and can't find the leak?
Newbie
Joined: Mar 2020
Posts: 4
Likes: 0
S500, GL550, SL550, E420
I keep getting the same message on my 2015 GL550. I add coolant/water, but also notice an additional expansion/recovery tank that is engine mounted in the center under the center motor cover. Do you add coolant to this as well? The manual is silent on this.
Junior Member
Joined: Nov 2014
Posts: 71
Likes: 5
2013 GL450
no I only add to the main coolant tank on the side of the engine bay, that would make the error message go away. At the end, for my car, the leak get gradually more severe to a point I have to add every week, they did find a crack in the radiator, changing the radiator fixed it.
